1. Field of the Invention
The present invention relates to a vessel for metallurgical purposes and in particular, a vessel for molten metals.
2. Description of the Related Art
Vessels for metallurgical purposes are used to transport molten metals, such as pig iron, from the blast furnace to the pig iron mixer or from the pig iron mixer to the converter. The vessel can also be used as metallurgical treatment vessels. As requirements have increased with respect to the degree of purity and the reduction in dissolved gas content of the molten metal, vacuum treatment has a more important method. In the vacuum treatment method, for reasons relating to the process, operation is conducted with a high overheating temperature. This results in especially high thermal loading of the treatment vessel. In vessels of conventional construction, the increased loading of weight and heat combined can lead to undesirable deformations. This is especially true for vessels having oval cross sections. The distortions can be so great as to cause constrictions in the area of the reinforcing or stiffening rings. Moreover, the carrying trunnions can become skewed so that difficulties occur when fitting the crane hook into the loops.
DE 29 01 011 B1 discloses a carrying trunnion fastening and bearing pin fastening for casting ladles in which the bearing pin projects into a cut-out in the casing of the casting ladle by the ladle foot and is welded to the edge of the cut-out. A rectangular fastening plate is fitted to the side of the bearing pin. The fastening plate is arranged between two stiffening rings which are fastened to the casing of the casting ladle. The plate is welded to the casing and to the stiffening rings. The fastening plate, which is cast integral with the bearing pin in a known manner, is provided at each of its lateral edges with a leg which is cast integral thereto. Each leg extends between the stiffening rings, and is welded to the casing approximately vertical to the fastening plate.
This bearing pin fastening arrangement is simple to construct and economical to manufacture. This arrangement also makes it easier to check for cracks or the like because only four circumferentially extending weld seams are required. The weld seams are easily accessible from the outside and can therefore be easily checked by ultrasound or other similar devices.